Why Cut

Cut was created to take advantage of people’s growing presence online and the use of web technologies in behavioral and social science research. Broadly, I aimed for two things:

  • Usability: Make it easy to use engaging, sophisticated research instruments in studies, beyond simple multiple-choice questions and scales. Some tools built by psychologists are too narrow in their use. Others are so general that they take extensive effort to learn. A balance between these two poles was needed.

  • Adaptability: Run these instruments on any device. People today use their phones more than their computers for most things outside work. Phones also reach a much larger population, in arguably more ecologically valid settings, at much lower cost. No one studying modern humans can ignore mobile devices.

Both aims still guide the work. A third has been added since: lining up what people do in a study with how they live, by joining task data with the sleep, heart-rate and activity data their own wearables already record.

History

Cut, 2014–2018. The first version had live multiplayer ultimatum and dictator games over WebSockets, computer opponents, game and study-flow designers, MTurk management, and several languages. A second version (around 2018) moved study design into a JSON editor. Both are retired.

Lens, 2018–present. Lens kept Cut’s idea of describing a whole study in one JSON file and made it run well on phones. It has collected data for published research, including a series of studies on the Ramadan fast. Lens 2.0 (October 2026) adds a study builder and a refreshed design for the tasks, and brings back Cut’s live two-player games: real-time pairing, Cut’s original computer strategies, a debrief that tells participants whether they played a person or a computer, and a full record of every move.

Jamasp, 2021–present. Jamasp recruits people who already own a Fitbit, through Prolific, and retrieves their wearable data automatically after they consent and link their device. A pilot ran with 41 participants over 65 days in 2025; its code and aggregate data are public.

People

  • Mostafa Salari Rad, The New School for Social Research: idea and design of Cut, Lens and Jamasp
  • Morteza Ansarinia: development of Cut and the original Lens
  • Arman Radmanesh: Jamasp, and later work on Lens

Support and research

Development was funded by The New School and the Association for Psychological Science (APS).

Research using these tools (summaries in the case studies on the home page):

  • Rad, M. S. (2025). Self-deprivation and cognition in Ramadan: Could fasting practice improve inhibitory control? Religion, Brain & Behavior, 234–259. doi:10.1080/2153599X.2025.2487277
  • Rad, M. S. (2023). From self-deprivation to cooperation: How Ramadan fasting influences risk-aversion and decisions in resource dilemmas. Current Research in Ecological and Social Psychology, 5, 100152. doi:10.1016/j.cresp.2023.100152
  • Rad, M. S., Ansarinia, M., & Shafir, E. (2023). Temporary self-deprivation can impair cognitive control: Evidence from the Ramadan fast. Personality and Social Psychology Bulletin, 49(3), 415–428. doi:10.1177/01461672211070385

Using Lens

Lens’s code is public. Build a study in the study builder, try the demos, or read the documentation and code on GitHub. If you use it in your research, cite the release your data came from.

I would love to hear your feedback.